1. The Field of the Invention
The present invention relates to a linking method under the mother and child block architecture for building check area and logic page of the child block for reducing the frequency of the erasing steps of the flash memory for extending the service life and to promote the operating speed thereof.
2. Description of the Related Art
The flash memory has been advantageously used in a variety of portable devices because of its unique characteristics, such as, low power consumption, non-volatile, high shock-tolerance and high storage density, gradually replacing EEPROM or other memory devices that requires a battery for operation thereof. Additionally, with the dramatic improvement of the semi-conductor technologies, the flash memory can achieve higher and better storage density and transmission speed, and accordingly the flash memory desirably replaces the traditional storage media, such as the hard disk driver in many applications.
However, the flash memory has certain limitation, in that, requires new space management for storage system. Besides, a new erasing method is required for evenly erasing the storage area in order to reduce the frequency of erasing, and thus the service life of the flash memory can be substantially extended and the power consumption of the system can be accordingly reduced. In the storage system of the flash memory, an inappropriate management causes an increase in the cost and cuts the service life of the flash memory short.
Referring to FIGS. 1, 2, 3, 4, 5 and 6, a conventional writing method is shown. As shown in FIGS. 1, 2, 3, 4, 5 and 6, the manager is ready for writing two pages into the flash memory from page 3 of block 0, the flash memory will find a new block, block 1B and defines block 0 as an old block, block 0A. Next, the page above page 3 of block 0A to block 1B is moved, and then the manager writes the page into page 3 and 4 of block 1B, then moves the page below page 4 of block 0A to block 1B, and then erases block 0A and replaces it by the block 1B to complete the writing step.
However, based on the physical characteristics of the flash memory, damage to the internal structure of the flash memory can easily occur after one million times of erasing steps. Accordingly, for extending the service life of the flash memory, the frequency of the erasing steps must be reduced. As described above, to write data, the flash memory has to locate a new block and erase the old one, in doing so, after one million erasure steps, the flash memory get easily damaged. Accordingly, finding a way to reduce the frequency of erasing steps of the flash memory for extending the service life thereof has become a priority in the field.